“Every 10 absences lowers average mathematics achievement equivalent to the difference between having a novice teacher and one with a bit more experience,” Raegen Miller, the report’s author, writes, citing a 2008 study.

Teachers who work in high-poverty and high-minority schools are absent more often, CAP reports.“It’s plausible that achievement gaps can be attributed, in part, to a teacher attendance gap,” writes Miller.

Not surprisingly, the more paid sick leave teachers get, the more they use. The report recommends giving teachers at least seven paid sick days per year, but limiting excused absences and using incentives to discourage “frivolous” use of paid leave.